The invention relates to a circular storage container for granular materials (hereafter sometimes "fill") having a central support column. A top-loading filling device is rotatable about the central axis and vertically movable along the column. A lateral conveyor is rotatable about the column and connected to the filling device via a telescopic, vertically extendable feed pipe. The support column, constructed of ring plates, has a central discharge shaft and guide rails affixed to its exterior for a hoisting and rotating apparatus, and the ring plates have a downward-slanting, wedge-shaped outer edge section.
In known large-scale silos of this type as disclosed in the Dutch patent application No. 8103486 a filling device and a crane bridge together with the lateral conveyor revolve around the central axis of the silo. The granular material drops through a feed pipe, which extends to a level just above the top of the fill in the silo, and is moved radially outward by the horizontal lateral conveyor. The lateral conveyor remains in a horizontal position as it is raised with the rising level of fill in the silo.
For removing the fill from the silo both screws of the lateral conveyor are counterrotated to draw the fill radially inward to where it drops past the ring plates through a central discharge shaft for further removal by a third screw conveyor. The ring plates are vertically spaced, arranged to define the central column and each has a horizontal surface of sufficient width so that the granular material thereon comes to rest in the form of the alluvial cone for the material in question. Thus, the material drops into the discharge shaft only when forced radially inward by the double screw conveyor.
The ring plates are reinforced by a downward-slanting outer edge. This can cause clogging when the lateral conveyor forces the granular material against the slanted edge during the removal process. Consequently, support columns constructed of ring plates, though proven to be highly advantageous as compared with other constructions serving the same purpose, are suited only for granular materials of the kind which do not tend to agglomerate.